1. Field of the Invention
This invention relates generally to automotive fluid systems and methods of use and more particularly to a brake fluid exchange system and method of use.
2. Description of Related Art
The following art defines the present state of this field:
Dyke, U.S. Pat. No. 3,548,978 describes an apparatus that permits a single operator, with a minimal amount of labor, to bleed trapped air from the hydraulic brake system of a vehicle. A mobile carrier carries a brake fluid auxiliary supply source with a pump extending to the interior of the source to pump fluid through a pump line to the fluid reservoir of a master cylinder of the system which in turn extends to a wheel cylinder having a bleed valve port. A universal type connecting sealer may join the pump line for securing the pump line to the master cylinder about a filler opening extending to the reservoir. A discharge tube is fitted to bleed valve port and extends to a hand carriable discharge reservoir.
Butler et al., U.S. Pat. No. 4,415,071 describes a control unit affixed to an adjustable stand mounted on a platform on wheels, having an electrical on/off switch which controls the vacuum pump of the extractor unit, a brake fluid and air extractor control valve which controls the flow of air and brake fluid being extracted from the master cylinder and brake system, a brake fluid application control valve which controls the flow of brake fluid (free of air) from the brake fluid reservoir container (with bracket) affixed on top of the control unit, a vacuum meter indicator which indicates the amount of vacuum present, and a master cylinder brake reservoir top with U-bolt which fit securely over the master cylinder of an automobile or truck. The control unit is connected to the master cylinder brake reservoir top by a heavy duty dual function extractor/application hose. The master cylinder brake reservoir top can be modified to fit other motor vehicles. An extractor unit mounted on a platform with wheels, has a vacuum pump which creates a suction action for pulling brake fluid and air out of the brake system, an extractor brake fluid collection container (with holes to reduce pressure) with bracket to hold the collection container, a junction box for electrical connections, a heavy duty extraction hose which connects the extractor unit to the control unit, and a collection hose which connects the collection container to the vacuum pump.
Brown, U.S. Pat. No. 5,291,968 describes an automatic transmission fluid change apparatus including a drain pan and associated holding tank for collecting and retaining used fluid recovered from an automatic transmission. A new fluid reservoir is provided within the apparatus to contain the quantity of new fluid required for a complete change of fluid in the transmission. To accomplish a complete change of fluid in the automatic transmission, the transmission pan and filter are removed and new fluid is pumped from the new fluid reservoir to the transmission orifice to which the outlet tube of the filter is typically coupled. The vehicle engine is simultaneously run at idle speed to circulate the new fluid throughout the transmission, thereby forcing all used fluid out of the transmission for collection and storage in the holding tank.
Knorr, U.S. Pat. No. 5,415,247 describes an automotive fluid exchange system wherein new fluid (such as power steering fluid) is simultaneously exchanged with the used fluid. First and second fluid conduits having first and second pumps disposed therein, respectively, provide the passageway between an engine compartment and a container for the new and used fluid, respectively. The two pumps are selectively actuable by a respective, conventional toggle switch. Conventional jumper cables provide the power supply means to drive the pumps.
Oien, U.S. Pat. No. 5,497,864 describes a hydraulic brake bleeder apparatus for bleeding hydraulic brake fluid from a vehicle hydraulic brake system. The apparatus includes a vacuum pump for drawing brake fluid from a vehicle brake cylinder and a pneumatic motor for driving the vacuum pump. A brake fluid recovery reservoir is located beneath the vacuum pump for emptying hydraulic brake fluid drawn by the pump from a brake cylinder. A brake fluid supply container is provided for replenishing the master cylinder hydraulic brake fluid, which is drawn from the brake cylinders during a bleeding operation.
Lee et al., U.S. Pat. No. 5,964,326 describes an apparatus for bleeding and refilling hydraulic brake systems, particularly, automotive hydraulic brake system, including a bleeding unit and a refilling unit. The bleeding unit comprises a peristaltic pump having an inlet and outlet tubing for removing brake fluid and entrapped air in a hydraulic system. A collection container is provided for holding the brake fluid removed. A first electronic timer operates the pump for a predetermined length of time. An opto-sensor attached to the inlet tubing serves as an air bubble detector, on each air bubble detected, a signal is issued to start a second electronic timer which operates the pump for an additional predetermined length of time simultaneously with the first timer. When the first timer almost reaches resetting, each air bubbles detected, thereafter, will trigger the second timer to operate the pump until no more air bubbles are detected. The output signal from the opto-sensor also activates a LED and an electronic beeper to indicate the presence of each air bubble. A bleeder valve adapter is provided for preventing air leak past the threads of the bleeder valve during bleeding. The refilling unit includes a peristaltic pump having an inlet and an outlet tubing for delivering new brake fluid to a master cylinder reservoir. An electronic timer operates the pump for a predetermined length of time so as to prime the refilling unit before refilling. A first capacitive proximity sensor serving as a fluid level controller is clamped together with the outlet tubing to the master cylinder reservoir by a reservoir clamp. A second capacitive proximity sensor serving as a flow detector is attached to the inlet tubing. When flow interruption such as air or low new brake fluid level is detected, the second capacitive proximity sensor outputs a signal to light a LED and to activate an electronic beeper to indicate flow interruption. A LED controlled by the first capacitive proximity sensor is used to indicate the new brake fluid level in the master cylinder reservoir during bleeding. A collection container is provided for holding the brake fluid removed during priming of the refilling unit.
Hollub et al., U.S. Pat. No. 6,206,055 describes an apparatus and method for removing, flushing contaminants from and replacing vehicle brake fluid. The apparatus has storage tanks for fresh and waste hydraulic fluid, a fill pump to pump hydraulic fresh hydraulic fluid to the vehicle braking system, an adapter for sealably connecting a fill hose to the master cylinder, a suction pump to suction used hydraulic fluid from the vehicle braking system to the waste fluid tank, a suction hose for suctioning fluid out of the master cylinder and hoses for connecting the waste fluid tank to the bleeder valves located at the vehicle wheels. A by-pass valve is provided between the fill pump and master cylinder to by-pass fluid when the fill hose reaches or exceeds a predetermined level. A computer and ancillary electrical and fluid connections between the various parts of the apparatus and the hydraulic fluid system of a vehicle are also utilized. The apparatus can also be used when replacing the master cylinder or when replacing fluid in other hydraulic systems (i.e. hydraulic clutch).
Hollub, U.S. Pat. No. 6,302,167 describes an apparatus and method for removing and flushing hydraulic fluid and contaminants from a vehicle's or other equipment's hydraulic system, and refilling the hydraulic system with new fluid. The apparatus has a vacuum pump to remove old hydraulic fluid from the master cylinder (reservoir) and a manifold and hose system to allow all bleeder valves and the ABS valves to be vacuumed at the same time through a hose system to a waste fluid container in the apparatus, a reversing vacuum pump to transfer waste fluid from the waste fluid container in the apparatus to an exterior storage tank, a reversing fill pump to pump new fluid from the new fluid container (in the apparatus) to the universal master cylinder adapter which connects the fill hose to the master cylinder, a combination of surging fill flow and surging vacuum out flow to produce a safe rapid removal of old fluid and refill of new fluid, a cross venting system to keep moisture and other contaminants from entering the new fluid container and to keep either the new fluid or the waste fluid container from venting fumes to the atmosphere. The apparatus also has sensors to detect and correct pressures and vacuum for safety and pump life. The apparatus also has a sensor to detect fluid levels in the waste fluid container in the apparatus, and a sensor to detect the availability of new fluid available for the service. The apparatus also provides a monitored leak containment area in the bottom of the apparatus to contain any leaks and advise the service provider of a leaking condition. The vacuum pump and vacuum wand can be used to clean out the containment area.
Erwin et al., U.S. Pat. No. 6,443,192 describes a method and an apparatus for loading a tank with brake fluid in an air-free manner which is accomplished by providing a flexible diaphragm in a tank and vacuuming air out underneath the diaphragm to draw new fluid into the tank so that it can be loaded for use in pressurized flushing of brake systems on vehicles. Another aspect of the method and apparatus is an indicator on the top of the tank which warns the user when the tank is almost out of new brake fluid in order to avoid the problem in the prior art systems of running out of new brake fluid during the flushing process.
Erwin et al., U.S. Pat. No. 6,536,486 describes a method of flushing the brake system of a vehicle by administering new brake fluid to the master cylinder under pressure while at the same time suctioning with a clear wand old brake fluid from a particular bleeder valve on the vehicle with all the remaining valves closed. Once the particular valve has been adequately bled, new brake fluid will be seen coming out of the valve through the clear wand, and the valve should be closed. This procedure is repeated for each of the remaining valves one at a time until all of the bleeder valves on the vehicle have been bled. Ideally, the first valve selected should be the one furthest from the master cylinder and the last valve selected should be the one closest to the master cylinder.
Erwin et al., U.S. 2003/0037837 describes a method of flushing the brake system of a vehicle by administering new brake fluid to the master cylinder under pressure while at the same time suctioning with a clear wand old brake fluid from a particular bleeder valve on the vehicle with all the remaining valves closed. Once the particular valve has been adequately bled, new brake fluid will be seen coming out of the valve through the clear wand, and the valve should be closed. This procedure is repeated for each of the remaining valves one at a time until all of the bleeder valves on the vehicle have been bled. Ideally, the first valve selected should be the one furthest from the master cylinder and the last valve selected should be the one closest to the master cylinder.
Hollub et al., WO 01/25090 describes an apparatus and method for removing, flushing and replacing vehicle brake fluid. The apparatus has storage tanks for fresh and waste fluid, a fill pump, and adapter for connecting a fill hose to a master cylinder, a suction pump, a suction hose and a hose for connecting the waste fluid tank to bleeder valves located on the vehicle wheels.
Hollub et al., WO 01/51357 describes an apparatus and method for flushing hydraulic systems and refilling the hydraulic systems with new fluid. The apparatus has a vacuum pump for removal of old hydraulic fluid from a master cylinder and a manifold and hose system to allow bleeder valves and ABS valves to be vacuumed at the same time through a hose system to a waste fluid container in the apparatus and a reversing fill pump to pump new fluid from a new fluid container to a universal master cylinder adapter.
The prior art teaches a hydraulic brake bleeding apparatus, a device for bleeding brakes and refilling brake systems, an apparatus and method for changing automatic transmission fluid in motor vehicles, an automotive fluid exchange system, a hydraulic brake bleeder apparatus, an apparatus for bleeding and refilling hydraulic brake systems, an apparatus and method for removing and replacing vehicle hydraulic fluid, an apparatus and method for removing and replacing vehicular hydraulic fluid while flushing the hydraulic system, brake flush methods, a vehicle brake flush method and apparatus, an apparatus for removing and replacing hydraulic fluid, and an apparatus and method for flushing hydraulic brake systems, but does not teach the use of a sealed system using a pump that does not come into contact with brake fluid and wherein the brake fluid system does not require bleeding upon fluid change out. The present invention fulfills these needs and provides further related advantages as described in the following summary.